Process and apparatus for producing filled wafer blocks

Abstract

In a process in which cover sheets and/or coated wafer sheets are joined to form filled wafer blocks, each coated wafer sheet and, if desired, each cover sheet is moved in a stacking location from a lower position to an overlying upper position, the coated upper surface of each coated wafer sheet is joined to the underside of the cover sheet which is in the upper position and which, if desired, has previously been raised to the upper position, or to the underside of the coated wafer sheet which has previously been raised to the upper position, and each complete wafer block consisting of at least two sheets is moved from said upper position out of said stacking location. To increase the production rate, it is proposed that the successive coated wafer sheets for each wafer block or successive coated wafer sheets and cover sheets disposed between successive coated wafer sheets are successively and continuously fed one by one to the lower position in the stacking location, and at least part of the movement of each of said sheets to said lower position is performed while the next preceding sheet is being raised. It is also proposed to carry out the process by means of two helical conveyors, which have parallel axes of rotation, which are inclined from a normal on the plane of conveyance of the wafer sheet feeder and each of which has a lower convolution, an upper convolution, and an inclined step joining said upper and lower convolutions.

We claim: 
     
       1. A process of producing multi-layered filled wafer blocks consisting each of a plurality of superimposed sheets having an upper surface coated with a spreadable composition and a cover sheet at the top thereof, which comprises (a) successively and one by one feeding the cover sheet and the coated sheets of each wafer block to a predetermined lower position in a stacking location,   (b) successively and one by one raising the sheets from the lower position to a predetermined upper position in the stacking location until the coated sheets are joined to the superimposed sheets to form each wafer block in the upper position, and   (c) discharging each formed wafer block in the upper position from the stacking location,   (d) the sheets being fed continuously to the lower position and each sheet being fed into the lower position before a preceding one of the sheets has reached the upper position.   
     
     
       2. The process of claim 1, wherein each formed wafer block is discharged from the stacking location while a respective one of the cover sheets for the following one of the wafer blocks is fed to the lower position in the stacking location. 
     
     
       3. The process of claim 1, wherein each formed wafer block is discharged from the stacking location while a respective one of the cover sheets for a following one of the wafer blocks is raised to the upper position. 
     
     
       4. A process of producing multi-layered filled wafer blocks consisting each of a plurality of superimposed sheets having an upper surface coated with a spreadable composition and a cover sheet at the top thereof, which comprises (a) successively and one by one feeding the coated sheets of each wafer block to a predetermined lower position in a stacking location,   (b) separately and directly feeding the cover sheet for each wafer block to a predetermined upper position above the lower position,   (c) successively and one by one raising the coated sheets from the lower position to the upper position in the stacking location until the coated sheets are joined to the superimposed sheets to form each wafer block in the upper position, and   (d) discharging each formed wafer block in the upper position from the stacking location,   (e) the coated sheets being fed continuously to the lower position and each coated sheet being fed into the lower position before a preceding one of the coated sheets has reached the upper position.   
     
     
       5. The process of claim 4, wherein the cover sheet of each formed wafer block is fed to the upper position before a first one of the coated sheets for the wafer block has reached the upper position in the stacking location. 
     
     
       6. The process of claim 4, wherein each formed wafer block is discharged from the stacking location while a respective one of the cover sheets for a following one of the wafer blocks is fed to the upper position in the stacking location. 
     
     
       7. An apparatus for producing multi-layered filled wafer blocks consisting each of a plurality of superimposed sheets having an upper surface coated with a spreadable composition and a cover sheet at the top thereof, which comprises (a) a stacking station,   (b) sheet-feeding means leading to, and terminating ahead of, the stacking station for successively and one by one feeding a respective one of the cover sheets followed by the coated sheets for each one of the wafer blocks to a predetermined lower position in the stacking station,   (c) a wafer block discharge conveyor for discharging a respective one of the wafer blocks from a predetermined upper position above the lower position in the stacking station,   (d) sheet-raising means in the stacking station between the sheet-feeding means and the wafer block discharge conveyor for successively and one by one raising each sheet fed by the sheet-feeding means from the lower to the upper position until the coated sheets are joined to the superimposed sheets to form each wafer block in the upper position, the sheet-raising means comprising (1) two adjacent helical conveyors spaced transversely to the sheet-feeding means and rotatable about parallel axes in opposite senses, each one of the helical conveyors having a lower convolution associated with the lower position and an upper convolution axially spaced from the lower convolution and associated with the upper position, the helical conveyor convolutions being arranged successively and one by one to receive the fed sheets during the rotation of the conveyors, and   (2) an inclined step connecting the lower and upper convolutions, and     (e) a stop associated with each one of the helical conveyors and adapted to be raised and lowered into and out of a path for each one of the wafer blocks from the upper position to the wafer block discharge conveyor, the stop being so arranged that rotation of the associated helical conveyor successively and one by one raises the sheets along the stop.   
     
     
       8. The apparatus of claim 7, wherein the helical conveyor convolutions are axially spaced helical wire flights having axially spaced ends adjacent each other, the inclined step connecting the adjacent helical wire flight ends. 
     
     
       9. The apparatus of claim 8, further comprising friction-increasing means on an upper surface of the upper helical wire flights. 
     
     
       10. The apparatus of claim 7, wherein helical conveyor convolutions are inclined with respect to a plane of conveyance of the sheet-feeding means, the axes of the conveyors being inclined in the feeding direction from a normal on the conveyance plane. 
     
     
       11. The apparatus of claim 10, wherein the axes are inclined by an angle of 30° to 45°. 
     
     
       12. The apparatus of claim 11, wherein the axes are inclined by an angle of 5° to 15°. 
     
     
       13. The apparatus of claim 7, wherein the wafer block discharge conveyor has a plane of conveyance higher than a plane of conveyance of the sheet-feeding means. 
     
     
       14. An apparatus for producing multi-layered filled wafer blocks consisting each of a plurality of superimposed sheets having an upper surface coated with a spreadable composition and a cover sheet at the top thereof, which comprises (a) a stacking station,   (b) a first sheet-feeding means leading to, and terminating ahead of, the stacking station for successively and one by one feeding a respective one of the coated sheets to a predetermined lower position in the stacking station,   (c) a second sheet-feeding means leading to, and terminating ahead of, the stacking station for successively and one by one feeding a respective one of the cover sheets to a predetermined upper position above the lower position in the stacking station,   (d) a wafer block discharge conveyor for discharging a respective one of the wafer blocks from the upper position,   (e) sheet-raising means in the stacking station between the sheet-feeding means and the wafer block discharge conveyor for successively and one by one raising each coated sheet fed by the first sheet-feeding means from the lower to the upper position until the coated sheets are joined to the superimposed sheets to form each wafer block in the upper position, the sheet-raising means comprising (1) two adjacent helical conveyors spaced transversely to the sheet-feeding means and rotatable about parallel axes in opposite senses, each one of the helical conveyors having a lower convolution associated with the lower position and an upper convolution axially spaced from the lower convolution and associated with the upper position, the helical conveyor convolutions being arranged successively and one by one to receive the fed sheets during the rotation of the conveyors, and   (2) an inclined step connecting the lower and upper convolutions, and     (f) a stop associated with each one of the helical conveyors and adapted to be raised and lowered into and out of a path for each one of the wafer blocks from the upper position to the wafer block discharge conveyor, the stop being so arranged that rotation of the associated helical conveyor successively and one by one raises the sheets along the stop.   
     
     
       15. The apparatus of claim 14, wherein the helical conveyor convolutions are axially spaced helical wire flights having axially spaced ends adjacent each other, the inclined step connecting the adjacent helical wire flight ends. 
     
     
       16. The apparatus of claim 15, further comprising friction-increasing means on an upper surface of the upper helical wire flights. 
     
     
       17. The apparatus of claim 14, wherein helical conveyor convolutions are inclined with respect to a plane of conveyance of the sheet-feeding means, the axes of the conveyors being inclined in the feeding direction from a normal on the conveyance plane. 
     
     
       18. The apparatus of claim 17, wherein the axes are inclined by an angle of 3° to 45°. 
     
     
       19. The apparatus of claim 18, wherein the axes are inclined by an angle of 5° to 15°. 
     
     
       20. The apparatus of claim 14, wherein the wafer block discharge conveyor has a plane of conveyance higher than a plane of conveyance of the sheet-feeding means.